Building time is an important issue in material extrusion-based additive manufacturing because in such a process head repositioning is always required between deposition segments (contours and rasters). The length of head repositioning, usually referred to as tool-path airtime or non-productive time, can be minimized by applying optimization algorithms. A particular issue in this area is the size of the problem to be solved. In this work, this problem is detailed and a framework for its decomposition and simplification is presented. The framework was divided in four (4) main steps and was designed to be used with different optimization methods. The first step was designed with some innovative methods to reduce the problem size. Hybrid mixed integer linear programming (MILP) models were implemented to solve steps two (2) to four (4). Three cases of different complexities were analyzed and compared with the solution from a classic greedy optimization algorithm. The results show that the framework was effective in dealing with this problem and, particularly for the cases analyzed, it was possible to reduce the repositioning distance considerably over a non-optimized route and by greedy optimization (with the best case reaching 69% and 17.8%, respectively).

建立时间是基于材料挤压的增材制造中的重要问题，因为在这种工艺中，始终需要在沉积段（轮廓和栅格）之间重新定位喷头。头部重新定位的长度（通常称为刀具路径的飞行时间或非生产时间）可以通过应用优化算法来最小化。这方面的一个特殊问题是要解决的问题的规模。在这项工作中，详细说明了这个问题，并提出了一个分解和简化的框架。该框架分为四（4）个主要步骤，旨在与不同的优化方法一起使用。第一步设计了一些创新方法来减小问题的大小。实施混合混合整数线性规划（MILP）模型以解决步骤二（2）至四（4）。分析了三种不同复杂度的情况，并将其与经典贪婪优化算法的解决方案进行了比较。结果表明，该框架可以有效地解决此问题，尤其是对于所分析的情况，可以通过未优化的路线和贪婪的优化来大大减少重定位距离（最佳情况下分别达到69％和17.8） ％， 分别）。